Many factors affect the realization of optimal outcomes in congenital cardiac surgery. Among these, the technical performance of the surgeon may be one of the most important. Systematic methods for evaluating operative technical adequacy across diagnoses and centers are needed. The Technical Performance Score (TPS) is a novel tool for assessing technical competency based on widely available clinical and echocardiographic characteristics. Earlier studies from a single center have suggested that the TPS is useful in predicting both early- and mid-term outcomes. Using the infrastructure of the NHLBI's Pediatric Heart Network, under mentorship from Drs. del Nido and Newburger, I will analyze the impact of technical performance, as assessed by the TPS, on early and mid-term outcomes in a well-defined subset of common congenital cardiac operations for which relatively similar operative techniques are used across institutions. Hypothesis: TPS is an effective predictor of outcomes, including occurrence of postoperative adverse events, resource utilization, late mortality, and need for late re-interventions in anatomic areas intervened upon, after surgery for congenital cardiac defects. Our primary outcome is number of days alive and out of the hospital within 30 days of surgery. Our secondary outcomes are: 1) occurrence of e 1 early major postoperative adverse event; 2) days of intensive care unit (ICU) stay, hospital length of stay, and initial and total time on the ventilator; 3) mortality/transplant after dischare for index operation; 4) unplanned re- interventions after discharge from index operation, and 5) the contribution of each component of the procedure-specific TPS to outcomes, to further refine the instrument over time. Patients will be eligible for the study if they are infants d12 months undergoing 1 of 6 open heart procedures. Exclusion criteria include the presence of any major congenital or acquired extra-cardiac anomalies that could independently affect the likelihood of the subject meeting the primary endpoint. The TPS will be ranked as optimal (Class I), adequate (Class 2), or inadequate (Class 3), based upon echocardiographic criteria that are designed to capture the individual components of specific operations, as well as unplanned surgical or catheter-based re-interventions prior to discharge in the anatomic areas relevant to the surgical procedure. A PHN expert panel of surgeons, echocardiographers, and cardiologists will finalize the TPS elements for each operation using the RAND modified Delphi technique. Echocardiograms will be interpreted in a Core Laboratory. Data will be prospectively collected during hospitalization for the index operation and again at 12 months for interim medical history, including additional interventions or mortality that occurred after hospital discharge. A minimum of 150 to 310 subjects in each procedural category will be enrolled over 2 years, and we will obtain 1 year of follow-up after enrollment. This study will be the first multi-center prospective validation of a tool for self-assessment and quality improvement specific to the congenital heart surgery community.